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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
********************************************************************************
* Copyright (C) 2003-2008, International Business Machines Corporation
* and others. All Rights Reserved.
********************************************************************************
*
* File JAPANCAL.H
*
* Modification History:
*
* Date Name Description
* 05/13/2003 srl copied from gregocal.h
********************************************************************************
*/
#ifndef JAPANCAL_H
#define JAPANCAL_H
#include "unicode/utypes.h"
#if !UCONFIG_NO_FORMATTING
#include "unicode/calendar.h"
#include "unicode/gregocal.h"
U_NAMESPACE_BEGIN
/**
* Concrete class which provides the Japanese calendar.
* <P>
* <code>JapaneseCalendar</code> is a subclass of <code>GregorianCalendar</code>
* that numbers years and eras based on the reigns of the Japanese emperors.
* The Japanese calendar is identical to the Gregorian calendar in all respects
* except for the year and era. The ascension of each emperor to the throne
* begins a new era, and the years of that era are numbered starting with the
* year of ascension as year 1.
* <p>
* Note that in the year of an imperial ascension, there are two possible sets
* of year and era values: that for the old era and for the new. For example, a
* new era began on January 7, 1989 AD. Strictly speaking, the first six days
* of that year were in the Showa era, e.g. "January 6, 64 Showa", while the rest
* of the year was in the Heisei era, e.g. "January 7, 1 Heisei". This class
* handles this distinction correctly when computing dates. However, in lenient
* mode either form of date is acceptable as input.
* <p>
* In modern times, eras have started on January 8, 1868 AD, Gregorian (Meiji),
* July 30, 1912 (Taisho), December 25, 1926 (Showa), and January 7, 1989 (Heisei). Constants
* for these eras, suitable for use in the <code>UCAL_ERA</code> field, are provided
* in this class. Note that the <em>number</em> used for each era is more or
* less arbitrary. Currently, the era starting in 645 AD is era #0; however this
* may change in the future. Use the predefined constants rather than using actual,
* absolute numbers.
* <p>
* Since ICU4C 63, start date of each era is imported from CLDR. CLDR era data
* may contain tentative era in near future with placeholder names. By default,
* such era data is not enabled. ICU4C users who want to test the behavior of
* the future era can enable this one of following settings (in the priority
* order):
* <ol>
* <li>Environment variable <code>ICU_ENABLE_TENTATIVE_ERA=true</code>.</li>
* </nl>
* @internal
*/
class JapaneseCalendar : public GregorianCalendar {
public:
/**
* Check environment variable.
* @internal
*/
U_I18N_API static UBool U_EXPORT2 enableTentativeEra(void);
/**
* Useful constants for JapaneseCalendar.
* Exported for use by test code.
* @internal
*/
U_I18N_API static uint32_t U_EXPORT2 getCurrentEra(void); // the current era
/**
* Constructs a JapaneseCalendar based on the current time in the default time zone
* with the given locale.
*
* @param aLocale The given locale.
* @param success Indicates the status of JapaneseCalendar object construction.
* Returns U_ZERO_ERROR if constructed successfully.
* @stable ICU 2.0
*/
JapaneseCalendar(const Locale& aLocale, UErrorCode& success);
/**
* Destructor
* @internal
*/
virtual ~JapaneseCalendar();
/**
* Copy constructor
* @param source the object to be copied.
* @internal
*/
JapaneseCalendar(const JapaneseCalendar& source);
/**
* Default assignment operator
* @param right the object to be copied.
* @internal
*/
JapaneseCalendar& operator=(const JapaneseCalendar& right);
/**
* Create and return a polymorphic copy of this calendar.
* @return return a polymorphic copy of this calendar.
* @internal
*/
virtual JapaneseCalendar* clone() const;
/**
* Return the extended year defined by the current fields. In the
* Japanese calendar case, this is equal to the equivalent extended Gregorian year.
* @internal
*/
virtual int32_t handleGetExtendedYear();
/**
* Return the maximum value that this field could have, given the current date.
* @internal
*/
virtual int32_t getActualMaximum(UCalendarDateFields field, UErrorCode& status) const;
public:
/**
* Override Calendar Returns a unique class ID POLYMORPHICALLY. Pure virtual
* override. This method is to implement a simple version of RTTI, since not all C++
* compilers support genuine RTTI. Polymorphic operator==() and clone() methods call
* this method.
*
* @return The class ID for this object. All objects of a given class have the
* same class ID. Objects of other classes have different class IDs.
* @internal
*/
virtual UClassID getDynamicClassID(void) const;
/**
* Return the class ID for this class. This is useful only for comparing to a return
* value from getDynamicClassID(). For example:
*
* Base* polymorphic_pointer = createPolymorphicObject();
* if (polymorphic_pointer->getDynamicClassID() ==
* Derived::getStaticClassID()) ...
*
* @return The class ID for all objects of this class.
* @internal
*/
U_I18N_API static UClassID U_EXPORT2 getStaticClassID(void);
/**
* return the calendar type, "japanese".
*
* @return calendar type
* @internal
*/
virtual const char * getType() const;
/**
* @return false - no default century in Japanese
* @internal
*/
virtual UBool haveDefaultCentury() const;
/**
* Not used - no default century.
* @internal
*/
virtual UDate defaultCenturyStart() const;
/**
* Not used - no default century.
* @internal
*/
virtual int32_t defaultCenturyStartYear() const;
private:
JapaneseCalendar(); // default constructor not implemented
protected:
/**
* Calculate the era for internal computation
* @internal
*/
virtual int32_t internalGetEra() const;
/**
* Compute fields from the JD
* @internal
*/
virtual void handleComputeFields(int32_t julianDay, UErrorCode& status);
/**
* Calculate the limit for a specified type of limit and field
* @internal
*/
virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const;
/***
* Called by computeJulianDay. Returns the default month (0-based) for the year,
* taking year and era into account. Will return the first month of the given era, if
* the current year is an ascension year.
* @param eyear the extended year
* @internal
*/
virtual int32_t getDefaultMonthInYear(int32_t eyear);
/***
* Called by computeJulianDay. Returns the default day (1-based) for the month,
* taking currently-set year and era into account. Will return the first day of the given
* era, if the current month is an ascension year and month.
* @param eyear the extended year
* @param mon the month in the year
* @internal
*/
virtual int32_t getDefaultDayInMonth(int32_t eyear, int32_t month);
};
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_FORMATTING */
#endif
//eof